It is recommended that drinking water contain 1.6 ppm fluo- ride (f) to prevent tooth decay. consider a cylindrical reservoir with a diameter of 4.50 x 10' m and a depth of 10.0 m. (the volume is rh, where r is the radius and h is the height.) how many grams of f should be added to give 1.6 ppm? fluoride is provided by hydrogen hexafluorosilicate, h. sif. how many grams of h sif contain this much f?

32,127.02 grams of hydrogen hexafluorosilicate will contain this 25,434  grams of F.

Explanation:

Volume of cylindrical reservoir = V

Radius of the cylindrical reservoir = r = d/2

d = diameter of the cylindrical reservoir = d =

r = d/2 = 22.5 m

Depth of the reservoir = h =  10.0 m

Volume of water cylindrical reservoir : V

Density of water,d = 1 kg/L

Mass of water cylindrical reservoir =  m

1.6 kilogram of fluorine per million kilograms of water. (Given)

Concentration of fluorine in water = 1.6 kg/ 1000,000 kg of water

In 1000,000 kg of water = 1.6 kg of fluorine

Then of water have x mass of fluorine:

15,896,250 kg water of contains mass 25.434 kg of fluorine.

25.434 kg = 25434 g

25,434  grams of fluorine  should be added to give 1.6 ppm.

Percentage of fluorine in hydrogen hexafluorosilicate :

Molar mass hydrogen hexafluorosilicate = 144 g/mol

Total mass of hydrogen hexafluorosilicate = m'

m' = 32,127.02 g

32,127.02 grams of hydrogen hexafluorosilicate will contain this 25,434  grams of F.

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.